Antarctic deserts

McKnight, D. M., G. R. Aiken, and R. L. Smith. 1991. Aquatic fulvic acids in microbially based ecosystems Results from two Antarctic desert lakes. Limnology and Oceanography 36 998-1006. 

Friedmann, I. and Ocampo, R., 1976. Endolithic blue-green algae in the Dry Valleys Primary producers in the Antarctic desert ecosystem. Science 193 1247—1249. 

Banerjee, M., Whitton, B.A. and Wynn-Williams, D.D. (2000a) Surface phosphomonoesterase activity of a natural immobilized system Chroococcidiopsis in an Antarctic desert rock. Journal of Applied Phycology 1 2, 549-552... 

Friedman I, Rafter A, Smith GI (1995) A thermeil, isotopic, and chemical study of Lake Vanda and Don Juan Pond, Antarctica. In Elliot DH, Blaisdell GL (eds) Contributions to Antarctic Research IV. Antarctic Research Series, vol. 67—. American Geophysical Union, Washington, DC, pp 177-194 Friedmemn El (1977) Microorganisms in Antarctic desert rocks from dry vrilleys and Dufek Massif. Antarctic J US 12(4) 26-29... 

Taking into account the electrochemical nature of the atmospheric corrosion process it is absolutely necessary to use the concept of Time of Wetness (TOW). It is a concept commonly used in atmospheric corrosion of metallic materials and refers to the time when the metal is sufficiently wet for corrosion reaction to occur, that is, when an electrolyte is present in the metallic surface. Under the particular characteristics of atmospheric corrosion there are time periods where corrosion could not occur due to the absence of an electrolyte in the metallic surface. The lowest outdoor TOW values are observed in the desert regions, as also in the Antarctic and Arctic regions. Atmospheric corrosion rates of metals at these climatic conditions are also very low and in the case of cold regions, the increase of temperature leads to the increase of TOW and corrosion rate [11], In principle, TOW is a parameter that depends upon both the climatic conditions and in the characteristics of the metallic surface. 

Priscu JC, Fritsen CH, Adams EE, Giovannoni SJ, Paerl HW, McKay CP, Doran PT, Gordon DA, Lanoil BD, Pinckney JL (1998) Perennial Antarctic lake ice An oasis for life in a polar desert. Science 280 2095-2098... 

McFall-Ngai, M., and J. Horwitz (1990). A comparative study of the thermal stability of the vertebrate eye lens Antarctic fish to the desert iguana. Exp. Eye Res. 50 703-709. 

Friedmann, E. I. (1982). Endolithic microorganisms in the Antarctic cold desert. Science, 215, 1045-53. 

Table I. Numbers of Classifled Non-Antarctic Meteorite Falls and Finds, Including Those from Hot and Cold Deserts...

Studies of 16S rDNA sequences obtained from clone libraries generated from PCR amplified 16S rDNA have included a broad selection of different environments from different parts of the world, such as marine sites (Atlantic, Pacific, Antarctic Sea), freshwater lakes and sewage plants, groundwater, terrestrial sites (deserts, peat bogs, forrested soil, rocks), human infected tissues, plant surfaces and the rhizosphere of different plants, as well as the gut content fi om invertertebrates and vertebrates (to name the most well studied sites). Due to space limitations only a few references on 16S rDNA environmental clone libraries will be included in the summary of the most importan results ... 

Priscu JC (ed) (1998) Ecosystem dynamics in a polar desert the McMurdo dry valleys, Antarctica. Antarctic Research Series, vol. 72. American Geophysical Union, Washington, DC Pyne SJ (1986) The ice A journey to Antarctica. University of Iowa Press. 

The microscopic particles are small enough to rise into the upper troposphere (up to 10 km above the surface of the Earth) and into the stratosphere (10-50 km above the surface) where they may reside for several years before they are eventually removed by meteoric precipitation. During their residence in the stratosphere the microscopic dust particles are transported widely over the Earth. The stratospheric dust particles in the Antarctic and Greenland ice cores are insoluble in water and are composed of clay minerals (Thompson 1977a, b Kumai 1997) and x-ray amorphous oxides and hydroxides aU of which were presumably derived from soil and regohth exposed in deserts and around receding ice sheets at the end of the Pleistocene. 

The presence of a fusion crust, the color and shape of the surface, the presence of metallic grains, and the unusual densities, in most cases, permit meteorite specimens to be distinguished from terrestrial boulders. These criteria apply to meteorite specimens that occur not only in the cold desert of Antarctica, but also to those that are collected in the hot deserts of the world, and in all other places where meteorites can be found. Even though tens of thousands of meteorite specimens have been collected on the East Antarctic ice sheet, Antarctica is not receiving a higher flux of meteorites compared to other areas of the Earth. The apparent abundance of meteorites is caused primarily by their better preservation in the ice and by the dynamics of the East Antarctic ice sheet. 

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